An artificial satellite (mass m) of a planet (mass M) revolves in a circular orbit whose radius is n times the radius R of the planet in the process of motion the satellite experiences a slight resistance due to cosmic dust. Assuming the force of resistance on satellite to depend on velocity as `F=av^(2)` where 'a' is a constant caculate how long the satellite will stay in the space before it falls on to the planet's surface.

Answer

`(m)/(alphasqrt(gR))(sqrt(eta)-1)`